Rock-drill.



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/v/ n /W 9, 0 t N A No. 879,971. PATENTED FEB. 25, 1908.

B. H. LOGKE. v

ROCK DRILL.

APPLIOATION FILED JULY l0. 1967.

2 SHEETS-SHEET 2.

Attest: Inventor:

b @WMM/K0@ W A ylw, @tw 75m/l Y partly in longitudina BRADFORD H. LOCKE, OF NEW YORK, N. Y.

ROCK-DRILL.

Specification of Letters Patent..

Patented Feb.' 25, 1908.

Application filed July 10. 1907. Serial No. 382.985.

To all whom it may concern:

Be it known that 1, BRADFORD H. Looxn, a citizen of the United States, residing in the borough of Manhattan, of the city of New York, in the State of New York, have invented certain new and useful Im rovements in Rock-Drills, of which the fo owing is a specification, reference being had to the accompanyingdrawings, forming a part hereof.

Under some conditions of use of mechanical rock vdrills the hole which is being drilled is liable to become clogged by--an accumulation of mud and the o eration of the drill thereby interfered wit It is desirable, therefore, to-provide means whereby such accumulation of mud may be prevented, and it is the object of this invention to rovide means for this urpose which shall e efiicient and reliable in operation and shall be especially applicable to electrically operated rock drills in the operation of which there is involved no source of steam or compressed air to be drawn upon for the purpose of clearin' out the hole.

n accordance with the invention there is combined with the drill mechanism a reservoir in which air is compressed by the operation of the drill and from which the air thus compressed ma be directed from time to time through t e drill to or nearly to the bottom of the hole to expel the mud there- 'from through the space around the drill stock. On account of the varying conditions of use and also that the operator may know when the discharge of the mud is to take place, it is preferable to have the air admitted at the will of the operator rather thanl automatically.

The invention will be more fully explained hereinafter withreference to the accom anying drawings in which it is illustrate and in which- Figure 1 is a view artly in elevation and partly in longitudinal central section of so much of an electrically operated drill as is necessary to enable the ap lication of the present improvement to e understood. Fig. 2 is a detail view in longitudinal central section, partly broken out, showing the drill stock, one end of which is shown 1n Fig. 1. Fig-.3 is a detail view, "artly in elevation and Fcentral section, on a arger scale than Fig. 1, showing particularly the means for com ressing air and discharging it into the dril hole.

The invention isillustrated in the drawings as applied to an electrically operated rock drill of Well known construction in which the drill piston a, driven forward 'by a spring b, is retracted by a cam c secured to the piston and cooperating with a cam ball d held frictionally by a floating ring d in a geared sleeve e. The latter is driven through a pinion e from a suitable electric motormounted on the frame of the drill. The cylinder a is extended backward be ond the cam c and receives, in the back cy 'nder g, 'a bushing a, which, so far as the present invention is concerned, virtually forms a part of the piston. All of the parts thus far referred to are arranged and operated in the usual manner and need not be further described herein.

The piston has formed therein a longitudinal channel or bore a2, preferably axial, which vcommunicates with a longitudinal channel or bore h in the drill stock h and provided with a port or opening h2 near the drill head. The rear portion of the bore or channel a2 is enlarged to form a cylinder a3 in which fits a tube i extended from the back cylinder cap k. The latter instead of being a simple plate, as heretofore, preferablyforms one wall of a reservoir 7c. An air inlet valve Z, carried by the reservoirk, permits air to be drawn by the forward movement of the piston a into .the space g within the back cylinder g, and an outlet valve m, also carr1ed by the reservoir 7c', permits the air which is compressed in the space g by the backward movement of the piston to be discharged into the reservoir. In order that the air which is thus com ressed in the reservoir k maybe discharge at intervals throu h the piston a and drlll stock h into the dri l hole near the he'ad of the drill, the tube 'i is' preferably extended rearwardly into the reservoir 1c', as at i', its bore belng somewhat enlarged to receive a piston valve 'fn and its wall being provided with one or more ports i2. The stem fn. of the piston valve n is extended beyond the wall of the reservoir vlc so that it may be provided with a handle n2 or other means by which the piston valve can be drawn back against the tension of the spring 'n3 to such an extent as 'to uncover the ports i2 and permit the air, under :compression in the reservoir kf, to pass through the tube i into the channel a2 of the piston and the channel h of the drill stock and be discharged through the port or opening h near the head of the drill. A clean-out for the reservoir may be provided at o.

fcylinder, a valve to admit air from the cyl- As 4thereciprocations of the piston are rapid` the compression of the air in the reservoir to any desired degree is quickly attained, and the dischar e 'of the air under' compression into the dri l hole near its bottorn will drive out the mud accumulated therein. In order that the dischar e of the mud may not take place unexpected y to the drill operator, and also that it may take place at such times as re uired, it is preferable to provide for the'disc arge of the air from the reservoir at the'will of the operator.

It Will be obvious that varlous changes in details of`construction and arrangement may be made to suit different conditions of operation Without departing from the spirit of the invention.

I claim as 'my invention:

1. In a rock drill,fthe combination of a reciprocatin piston,a reservoir in-Which air is compresse by the reciprocating piston, and

vmeans to discharge the air therefrom into the drill hole.

2. In a rock drill, the combination of aback cylinder', a piston reciprocating therein, an air reservoir carried by the cylinder, an inlet valve to'admit air into the back end of the inder intov the reservoir, and means to diswhich air is compressed bythe reciprocationV of the piston, and means to discharge air from the reservoir into the drill hole.

4. In a rock drill, the combination of a rey ciprocating piston having a' longitudinal channel, an air reservoir in Which air 1s com- 4 pressed by the reciprocations of the piston, a

tube connecting the air reservoir with the channel of the piston, a valve controlling the admission of air from the reservoir through jsaid tube to said channel, and'means to 0perate said valve.

5. In a rock drill, the combination of a re- I ciprocating piston having a longitudinal channel, a drill stock carried by sald piston and havin the channe in the piston and provided-with. an opening near the .drill head, an air reservoir 1n whlch air is compressed by the recip-A lrocations of the piston and means to discharge air from said reservoir through the channels ofthe piston and drill, stock into the afchannel communicating with.

drill hole.

This speciicationlsigned and witnessed this 2nd day of July, 1907. 1clhirge air from the reservoir -i-nto the drill I 3. vIn a rock drill, the combination of a rer ciprocating piston, a spring to drive the same orward, a cam secured to the piston, a geared BRADFORD H. LocKE.

l Signed in the presence otv ELLA J. KRUGER, AMBRosE L., OSHEA. 

